Elastic-fluid turbine.



E. THOMSON. ELASTIG FLUID TURBINE. APPLICATION FILED MAR. 3, 190e.

Patented May 4, 1909.

w l v Ir-lvenhor; Eihu Tomson,

M VJ

Witnesses z .UNITED OFFICE.

ELIHU TOMSQN, QF SWAMPSCOTT, MASSACHUSETTS, SSIGNOR TO GENERAE ELECTRIC To allgwhom 'it 'may cncem:

COMPANY, A CORPORATION'OF NEW YORK.

ELAs'rrc-FLUID TURB-INE, l

3e it known that I, ELIHU THOMSON, a c1t1zen of the United States, residing' at Sivampscott, countyof Essex, State of Massachusetts, have invented certain new and useful Improvements in Elastic-Fluid Turblnes, of which the following is a specification'.

The present invention relates to elasticfluid turbines, and has for yits object to imrove their constructlon, particular reference v eing made `to supporting and balancing the rotating memberfagainst end thrust, and to dispensing with the diaphragms nowcommonly used in certain types of maclunes to divide them into stages of expansion.

.ln the accompanying drawing, attached to and made av art of this' specification, is shown one of e embodiments of the invention, the illustration being en axial section of a multi-stage turbine of the jet type.

1 represents the inclosing casing-of the tur-v bine, and 2 a valve chest attached thereto.

number.

Steam or other elastic fluid is dischaed partially, depending uponthe type of inachine, the condi-tions of service, etc.

These bucketsare secured to holders, and the latter in turn are secured by bolts 6 to the casing. In addition to the admission nozzle or iluiddischarging device, there are stage nozzles or fluid-discharging devices 7, of which as many may be provided as desired.` The number of stages and stage nozzles can be increased or decreased as desired to meet the loadiconditions. The stage nozzles are or may be formed in an internal shoulder ofr projection formed on or carried by the inside of the casing. The inner surface of the shoulder co erates with the periphery of the drum to iivide the casi-ng into stages,V three 'being shown 'as iilus'trative of theinvention. Instead of ,1\ Specification of Letters Patent.' i

Application med laren a, 190s. serai No. 303,979'.

yBetween the rows of wheel bue ets PatentedMay 4, 1909.

making the nozzle structure integral with Athe casing, it ymay be separate `therefrom and bolted or otherwise secured to the-casing.

In oneend of the casing is a chamber 8 to receive theexha'ust, the said chamber being' connected hy'a conduit (not shown because it leads from the other side of the-chamber than that illustrated' in the sectional drawingl with the 'atmosphere orA with a condenser. v 1

A The wheel buckets are mounted on a drum or'rim 9 and may` lne-integral .therewith or separatel formed and attached thereto. The leftand end of the druml or wheel rim in the present illustration is supported by a,

disk 1() carried by the main shaft or spindle 11, which dis'k is shown as being integral with the drum, but it may be separable 1f desired and rigidly secured'thereto. To this disk the main shaft l1 is attached or formed integral therewith. The diameter of the drum is or may be increased in one or more ste s to accommodate the increased volume of 'uid as the pressure decreases, and also to increase the area of the disk 12 exposed to the low-pressure steam or other fluid. The

right-hand vend of the drum is supported and -centered by the\diskv 12 mounted, on sec'- ondary shaft 21 forming a continuation of 'on the bucket'drum to a greater or less extent. The 'disk 12 is shown las being com mon to the bucket andl balancing drums but' separate disks or supports may beprovided.

The cylindrical wal of the balancing drum extends longitudinally of the bucket drum and rotects thaty portion ofthe druml carryl .ing't el second-stage buckets from the effects It, how-I ol 'the fluid of higher temperature. ever, itis desired to increase the'temperature of the motive iiuid vin the stages of lower pressure, the chamber 13 may commu-vete Awith a stage of higher ressure. t

Between the periphery of .the balancing drumand the inner surface ol' the bucket drum are packings 14 and 15. By reason of.

this arrangement chambers 16 and '17 areprovided containing motive fluid at thepressure of the iirst stage, equalizii'ig passages 1S Y sure on the adjacent Wall of the balancing wear on the packings 14 and 15 is so slight as the same, and also by,reason of the arrangement of the chamber 22.

drum tends to move the latter and the secondary shaft 21 which supports it to the right.

The bucket drum is enlarged between the secondnndv third stages and the chamber 22 thus formed communicates with the wheel chamber 23 by means of the passage 24. The opposite walls of the chamber 22 are eX posed to thesaine pressure and hence the eilects thereonare equal and opposite. The entire right-hand side of the disk 12 is eX- posed to the pressure Vof steam or other niotive fluid in the adjacent chamber, and the pressure in said chamber is maintained theA same as that of the exliaust by one or more passages 25. ,y

` The balancing drum is .fastened to the secoiidary shaft 21 and the latter is capable of moving slightly to and fro witlirespect to the outer drum and the main shaft. It rotates liov'vevei' at the same rate of s eed as the drum and main shaft. Since t e relative amount ol longitudinal movement of the inner and outer drums is very small the to be disregarded.

The bu eket d rum is substantially.balanced l by reason of the fact that the steam pressures on opposite sides ofthe disk l() are changes due to changes in load, the pressures on op posito sides ol the diskand in the chamber correspondingly change There ishowever. a certain small amount of `thrust from left to right which must be eliminated to ob tain the best results.` This is taken care ol by suitable collars and bearings on.- the main shaft. 1

' The thrust on the balancing drum is'taken, care of by the following means: At the righthand end of the secondary shaft a small chamber 26 is provided containing Water, oil or-other lubricating medium. The l'luid admitted to the chamber is undera pressure equal to or superior to the resultant'end space between the moves to and fro-the rnoven'ientv being thrust on the balancingdrum, and the flow of the liquid is controlled by a-valve 27 normally held against its seat by the adjustable spring 28. rllie end of the shaft is preferably provided with a hardened steel plate and the end of' the valve is similarly arranged, the arts being exaggerated for the purpose of il ustration. As the shaft very slight-fthe valve is alternately opened As the pressure to admit fluid and closed to shut it olf. Fluid isv admitted by the conduit 29, and where Water is used it can be permitted to flow through and lubricate the bearing and exhaust with the steam from the ivheel buckets. Where oil is used it is best to provide a se arate return. 1

From "t ie construction described it'will be apparent that it is unnecessary to have any.,

very accurate adjustment of' the balancing drum, thereby greatly simplifying the construction of the turbine. The location ofthe bucket drum being iixed on the main shaft as to longitudinal movement, itv follows that the balancing drum can moveback and forth slightly without danger to the parts. Of course under this condition differences in pressures on opposite ends of the balancing drum would be brought about which would limit its movements. It will also be seenl thatin additionuto balancing the thrust on the bucket drum the balancing-drumrealby supports one `end of it and centers the saine, and this Without constraining the bucket drum in any Way. By supporting the buckets on a drum and locating the nozzles or fluid-discharging devices in rings which' closelyl encirclethe drum and cooperate therei'vit'h to form separate compartments or stages, I am enabled to dispense with the diaphragms now commonly used in in achines of the jet type. @Wing to the fact that the temperatures on opposite sides of' the disk .1()

are the saine, all warping is prevented.. v

There is a difference in temperature between yopposite ends ofthe balancing drum, but

this does no damage because it does not affect the alinement or .adjustment of the buckets.

by Letters Patent of. the United States, isf',-t

1. In an elastic-fluid turbine, the combine tion of buckets which are relatively rotata ble, an inclosing casing, and a means for bal# j ancing the thrust on vone set of buckets'comprising a member which is movable axially of the casing and also assists in'supporting one set of buckets.

2. In an elastic-fluidturbine, the lcombination of buckets which are relatively rotatable, an inclosing easing/f,v forthe buckets, and a meansv Within the'casing and acting on the rotating member for balancing the thrust thereon which responsive to changes in fluid res'sure within the casing and is movable independently 'of the buckets. 3. In an elastic-fluid turbine, the combination of a casing, buckets `carried thereby, a

` bucket-carrying drum, and means. for

ancing the thrust on the bucket drum, which' is movable axially and independently of the bucket drum. i

4. In an elastic fluid-turbine, the combination of a casing, relatively rotatable buckets inclosed thereby, la shaft carrying one set of buckets, and a drum for balancing the end thrust on one set of buckets, which ismovable longitudinally with respect to said shaft.

5. In an elastic-fluidturbine, the combination of a casing, buckets carried thereby, fluid-discharging devices,.a drum carrying the revolvingbuckets, a balancing Adrum located `.inside of the bucket drum, which .is-

1 movable 'axially with respect thereto, and a means for taking up the thrust on the balancing drum.

6. In an elastic-fluid turbine, the combina tion of a casing, Lfinid-discliarging devices carried thereby, a 4bucket-carrying drum which is rotated by the fluid from said devices, a main shaft, a means for sup orting the drum` from the main shaft, a ba ancing ancing drum, Which is mova drum, a secondary shaft su orting the balblie longitudinally with respectto the main shaft in response to pressure changes, and a lmeans for receiving the thrust of the secondary shaft.

7. In an elastic-fluid turbine, the combination of a casing, a bucket-carryingtdrum inclosed thereby, a shaft supporting the drum, means for preventing endwise movement thereof, a. balancing drumwhich supports and centers the bucket drum Without constraining its movements due to expansion and contraction, the said balancing drum being l free to move vslightly lin an axial, direction,

and a means arranged to receive the thrust of the balancing drum.-

- 8. In/an elastic-fluid turbine, the combination o f a casing, a bucket-carrying drum, a Wall carried. by the casing and supporting fluid-disqhalrging devi ``the Asaid Wall cooperating With the surface`of the drum to form sta es, a balancing drum 'extending in-y side of t e bucket drum, and a means for .taking up the thrust on the'balancing drum.

9. In an elastic-fluid turbine, the 'combination of a casing, a bucket-carrying drum,a

Wall carried by the casing and supporting.

fluid-discharging devices, the said wall coform stages, a balancing drum located inside of the bucket drum and movable longitudinally thereof to a limited extent, and a fluidpressure means for taking up the thrust on f "carried thereby, a bucket. carrying support Within the casing "which is rotated by they fluid from said devices, a main shaft on hich the support is'mounted, a balancing drum, a secondary shaft supporting the ball ancing drum which is .movable longitudinally with resp' ct to the main shaft, and means' for receiving the thrust of the secondary shaft comprising a source of fluid under pressure, and a-valve which is moved from its seat by the movement of the shaft to permit the fluid pressure to oppose the thrust.

12. In combination in an elastic fluid tur'- bine, a rotor element comprising' a Wheel .operatingwith the surface of the drum to mounted on the spindlevof the turbine, a diskv f mounted adjacent the wheel which is movable axially of saidwl-ieel and tends to balance the pressures thereon, a packing bef4 tween the periphery of the disk andthe rim of the Wheel, and a means for taking up the thrust on tlie disk.

In Witness whereof, I have hereunto set my hand this twenty, eighth day of February,

ELIHU THOMSON;

Witnesses JOHN A.. McMANUs, Jr. v HENRY O. WESTENDARP. 

